The House of Hades (Heroes of Olympus Book 4)

The fourth book in the Heroes of Olympus series follows Percy Jackson and Annabeth as they navigate the treacherous realm of Tartarus. Their quest is critical; failure means chaos on Earth. As they face deadly monsters at every turn, Hazel and the crew of the Argo II must make a difficult choice: intervene in a brewing war or rescue their friends. The Underworld presents relentless challenges, and evil lurks at every corner, testing their courage and loyalty.